The present invention relates generally to a label for a container, package or the like which has a removable portion having a temperature sensitive indicia thereon.
In the past, various attempts have been made to provide consumers with convenient methods of determining the temperature within a package or container. These applications have included the permanent attachment of the thermally sensitive element to the particular package or container. As such, the thermally sensitive element is not reusable or transferable.
U.S. Pat. No. 5,786,578 to Christy et al. describes a label having a thermochromatic ink temperature indicator which is attached to a microwaveable container. The label indicates temperatures which are xe2x80x9cOKxe2x80x9d or xe2x80x9cTOO HOT,xe2x80x9d depending on the temperature of the contents of the container.
U.S. Pat. No. 5,918,981 to Ribi describes several uses for thermochromatic inks. One embodiment is for a label which places the letter xe2x80x9cUNxe2x80x9d in thermochromatic ink before the word xe2x80x9cSAFExe2x80x9d in standard ink. If the temperature of the label rises above a set point, the letters xe2x80x9cUNxe2x80x9d become visible, signifying that the contents of the package to which the label is attached have become unacceptably hot. In another embodiment applies a stripe of thermochromatic ink to a container as a temperature indicator.
U.S. Pat. No. 3,864,976 to Parker describes an overwrap for a container. The overwrap is described as a thin plastic film onto which thermally sensitive ink has been printed.
U.S. Pat. No. 5,482,373 to Hutchinson describes the application of a thermometer to the side of a drink bottle, such as a soda can as shown in FIG. 1 or a beer bottle as shown in FIG. 3. The thermometer is shown as a label which can be purchased separately from the container whose temperature is to be monitored. The temperature sensitive element of the thermometer is described as a thermochromatic ink.
U.S. Pat. No. 2,308,087 to Lappala describes a temperature sensing label. The label is made of a clear film onto which temperature sensitive paint is applied. The clear film is then folded over onto itself to entrap the paint. Lappala describes applying the paint to form words which will then appear at a set temperature.
U.S. Pat. No. 4,878,588 to Ephraim shows a temperature indicator built into the side of a baby bottle. The temperature indicator consists of several cells of temperature sensitive liquid crystals, whose visual properties change at set temperatures.
The present invention contemplates a label for use on a package, container or the like having a thermally sensitive label or label portion which may be removed from the main body of the label to be applied to another container.
In one embodiment of the present invention, the label includes at least two plies, an outer ply and an inner ply. The interior surface of the outer ply and the outer surface of the second ply are permanently adhered to one another over a major portion thereof. A temperature sensing element is provided a one location on the outer ply. In the area of this portion of the label, the outer ply and the second ply are releaseably adhered to one another. The temperature sensing element is preferably created by a thermochromatic ink printed on the inside surface of the outer ply. A pressure sensitive reusable adhesive is provided to the interior surface of the outer ply over the thermochromatic ink.
The temperature sensing element may be defined by a series of perforations within the outer ply. This portion is removable from the inner ply of the label and the remaining portions of the outer ply. The temperature sensing element, thus, may be removed from the package or container and secured to a second container for temperature sensing. Depending on the strength and type of adhesive, the removable temperature sensing element may be repeatedly applied to various packages for sensing of the temperature of the packages or the goods therein.